Apparatus and method of recognizing external device in a communication system

ABSTRACT

An apparatus and a method of recognizing an external device in a portable terminal are provided. The apparatus includes a connector connected to the external device, and a controller configured to transmit a connection message, if the portable terminal is connected to the external device through the connector, the connection message asking whether the external device supports a second connection scheme to the external device by using a first connection scheme, configured to receive a connection response message as a response to the connection message from the external device, configured to determine based on the connection response message whether the external device supports the second connection scheme, and configured to recognize at least one device supporting the second connection scheme in the external device by activating the second connection scheme, if the external device supports the second connection scheme.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit under 35 U.S.C. §119(a) of a Koreanpatent application filed on May 21, 2013 in the Korean IntellectualProperty Office and assigned Serial No. 10-2013-0057279, the entiredisclosure of which is hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a communication system. Moreparticularly, the present disclosure relates to an apparatus and methodof recognizing an external device in a communication system.

BACKGROUND

Portable terminals, such as smartphones and tablets, provide a varietyof useful functions to users through a lot of applications. Therefore,the portable terminals are evolving toward devices that provide varioustypes of information, in addition to voice call information, via variousfunctions. Such a portable terminal is connected to an external deviceand outputs data to the external device or receives data from theexternal device by a data Input/Output (I/O) function.

To provide the data I/O function, the portable terminal and the externaldevice should be connected in a specific connection scheme, such asUniversal Serial Bus (USB) connectivity and Mobile High-Definition Link(MHL) connectivity. If the external device supports MHL connectivity andUSB connectivity, the portable terminal recognizes a USB device of theexternal device based on a resistance of a USB IDentifier (ID) pin.

However, since USB ID pins are limited resources, ACcessory Detection(ACD) values corresponding to the resistance values of the USB ID pinscannot be defined for all supported accessories. As a consequence, aportable terminal recognizes only a limited number of external devices,and may not recognize all external devices supporting USB connectivity.

FIG. 1 illustrates a configuration of a communication system accordingto the related art.

Referring to FIG. 1, the communication system includes a portableterminal 101 and an external device 103. When the external device 103 isconnected to the portable terminal 101 via a Universal Serial Bus (USB)cable 105, the external device 103 provides its specific function to theportable terminal 101. The external device 103 is called an accessoryand may be any of a TeleVision (TV), a monitor, a beam projector, akeyboard, a touch screen, a Personal Computer (PC), an audio player, anauxiliary battery, and any other similar and/or suitable electronicdevice. For example, if the external device 103 is a TV, then theexternal device 103 may provide a multimedia play function of receivingmultimedia data from the portable terminal 101 and displaying thereceived multimedia data.

When the portable terminal 101 is connected to the external device 103via the USB cable 105, the portable terminal 101 measures a resistanceof a pin corresponding to a USB IDentifier (ID), from among a pluralityof pins included in a connector of the portable terminal 101. Theportable terminal 101 determines the external device 103 based on themeasured resistance, referring to a table tabulating ACcessory Detection(ADC) values with respect to predetermined resistance values of USB IDs.Then the portable terminal 101 recognizes the external device 103 byperforming a USB host function.

The USB host function refers to a function that enables operationbetween portable terminals such as a Personal Digital Assistant (PDA),an MP3 player, and a portable phone, without intervention of a maincomputer. For example, the USB host function may include a data exchangefunction between the portable terminal 101 and the external device 103,and a battery charging function of the portable terminal 101, when theexternal device 103 is an auxiliary battery.

FIG. 2 is a table that tabulates ADC values versus the resistance valuesof USB ID pins according to the related art.

Referring to FIG. 2, a table 201 that tabulates ADC values versus theresistance values of USB ID pins includes ADC values 203 allocated to aplurality of accessories. For example, if a USB ID resistance is 28.7KΩ, the portable terminal 101 may detect an ADC value of 0x0E mapped tothe USB ID resistance 28.7 KΩ. If determining that the external device103 corresponds to Accessory 1 mapped to the ADC value 0x0E, then theportable terminal 101 may recognize the external device 103 byperforming the USB host function.

However, since USB ID pins are limited resources, ADC valuescorresponding to the resistance values of USB ID pins cannot be definedfor all supported accessories. Consequently, the portable terminal 101may recognize a limited number of accessories, because not allaccessories support USB connectivity. For example, the portable terminal101 may recognize only five types of accessories 203 preset in the table201 listing ADC values versus the resistance values of USB ID pins, andthus, may not recognize other types of accessories.

The above information is presented as background information only toassist with an understanding of the present disclosure. No determinationhas been made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the present disclosure.

SUMMARY

Aspects of the present disclosure are to address at least theabove-mentioned problems and/or disadvantages and to provide at leastthe advantages described below. Accordingly, an aspect of the presentdisclosure is to provide an apparatus and method of recognizing allexternal devices supporting Universal Serial Bus (USB) connectivity in acommunication system.

Another aspect of the present disclosure is to provide an apparatus andmethod of recognizing all external devices supporting USB connectivityusing Mobile High-Definition Link (MHL) connectivity in a communicationsystem.

Another aspect of the present disclosure is to provide an apparatus andmethod of recognizing all external devices supporting USB connectivityusing a Control BUS (CBUS) line, from among MHL lines, in acommunication system.

In accordance with an aspect of the present disclosure, an apparatus ofrecognizing an external device in a portable terminal is provided. Theapparatus includes a connector connected to the external device, and acontroller configured to transmit a connection message, if the portableterminal is connected to the external device through the connector, theconnection message asking whether the external device supports a secondconnection scheme to the external device by using a first connectionscheme, configured to receive a connection response message as aresponse to the connection message from the external device, configuredto determine based on the connection response message whether theexternal device supports the second connection scheme, and configured torecognize at least one device supporting the second connection scheme inthe external device by activating the second connection scheme, if theexternal device supports the second connection scheme.

In accordance with another aspect of the present disclosure, anapparatus of recognizing an external device in a portable terminal isprovided. The apparatus includes a connector connected to the externaldevice, and a controller configured to transmit a connection message, ifthe portable terminal is connected to the external device through theconnector, the connection message asking whether the external devicesupports USB connectivity to the external device by using MHLconnectivity via a CBUS line of the connector, configured to receive aconnection response message as a response to the connection message fromthe external device via the CBUS line, configured to determine based onthe connection response message whether the external device supports USBconnectivity, and configured to recognize at least one USB device of theexternal device by executing a USB host function, if the external devicesupports USB connectivity.

In accordance with another aspect of the present disclosure, anapparatus of recognizing a portable terminal in an external device isprovided. The apparatus includes a connector connected to the portabledevice, and a controller configured to receive a connection message, ifthe external device is connected to the portable terminal through theconnector, the connection message asking whether the external devicesupports a second connection scheme from the portable terminal by usinga first connection scheme, configured to generate a connection responsemessage indicating whether the external device supports the secondconnection scheme as a response to the connection message, andconfigured to transmit the connection response message to the portableterminal by the first connection scheme.

In accordance with another aspect of the present disclosure, anapparatus of recognizing a portable terminal in an external device isprovided. The apparatus includes a connector connected to the portabledevice, and a controller configured to receive a connection message, ifthe external device is connected to the portable terminal through theconnector, the connection message asking whether the external devicesupports USB connectivity from the portable terminal by MHL connectivityvia a CBUS line of the connector, configured to generate a connectionresponse message indicating whether the external device supports USBconnectivity as a response to the connection message, and configured totransmit the connection response message to the portable terminal viathe CBUS line.

In accordance with another aspect of the present disclosure, a method ofrecognizing an external device in a portable terminal is provided. Themethod includes transmitting, if the portable terminal is connected tothe external device through a connector, a connection message askingwhether the external device supports a second connection scheme to theexternal device by using a first connection scheme, receiving aconnection response message as a response to the connection message fromthe external device, determining based on the connection responsemessage whether the external device supports the second connectionscheme, and recognizing at least one device supporting the secondconnection scheme in the external device by activating the secondconnection scheme, if the external device supports the second connectionscheme.

In accordance with another aspect of the present disclosure, a method ofrecognizing an external device in a portable terminal is provided. Themethod includes transmitting, if the portable terminal is connected tothe external device through a connector, a connection message askingwhether the external device supports USB connectivity to the externaldevice by using MHL connectivity via a CBUS line of the connector,receiving a connection response message as a response to the connectionmessage from the external device via the CBUS line, determining based onthe connection response message whether the external device supports USBconnectivity, and recognizing at least one USB device of the externaldevice by executing a USB host function, if the external device supportsUSB connectivity.

In accordance with another aspect of the present disclosure, a method ofrecognizing a portable terminal in an external device is provided. Themethod includes receiving, if the external device is connected to theportable terminal through a connector, a connection message askingwhether the external device supports a second connection scheme from theportable terminal by using a first connection scheme, generating aconnection response message indicating whether the external devicesupports the second connection scheme as a response to the connectionmessage, and transmitting the connection response message to theportable terminal by using the first connection scheme.

In accordance with another aspect of the present disclosure, a method ofrecognizing a portable terminal in an external device is provided. Themethod includes receiving, if the external device is connected to theportable terminal through a connector, a connection message askingwhether the external device supports USB connectivity from the portableterminal by using MHL connectivity via a CBUS line of the connector,generating a connection response message indicating whether the externaldevice supports USB connectivity as a response to the connectionmessage, and transmitting the connection response message to theportable terminal via the CBUS line.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the present disclosure will be more apparent from thefollowing description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 illustrates a configuration of a communication system accordingto the related art;

FIG. 2 is a table that tabulates Accessory Detection (ADC) values versusthe resistance values of Universal Serial Bus (USB) IDentifier (ID) pinsaccording to the related art;

FIG. 3 illustrates a configuration of a communication system accordingto an embodiment of the present disclosure;

FIG. 4 illustrates lines between a portable terminal and an externaldevice in a communication system according to an embodiment of thepresent disclosure;

FIG. 5 is a block diagram of a portable terminal according to anembodiment of the present disclosure;

FIG. 6 is a block diagram of an external device according to anembodiment of the present disclosure;

FIG. 7 is a flowchart illustrating an operation of recognizing anexternal device in a communication system according to an embodiment ofthe present disclosure;

FIG. 8 is a flowchart illustrating an operation of recognizing anexternal device in a portable terminal according to an embodiment of thepresent disclosure;

FIG. 9 is a flowchart illustrating an operation of transmitting a USBconnection response message in an external device according to anembodiment of the present disclosure;

FIG. 10 illustrates a configuration of a communication system accordingto another embodiment of the present disclosure;

FIG. 11 illustrates lines between a portable terminal and an externaldevice in a communication system according to another embodiment of thepresent disclosure;

FIG. 12 is a block diagram of a portable terminal according to anotherembodiment of the present disclosure;

FIG. 13 is a block diagram of an external device according to anotherembodiment of the present disclosure;

FIG. 14 is a flowchart illustrating an operation of recognizing anexternal device in a communication system according to anotherembodiment of the present disclosure; and

FIG. 15 is a flowchart illustrating an operation of recognizing anexternal device in a portable terminal according to another embodimentof the present disclosure.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components, and structures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the present disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thepresent disclosure. In addition, descriptions of well-known functionsand constructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of the presentdisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of the presentdisclosure is provided for illustration purpose only and not for thepurpose of limiting the present disclosure as defined by the appendedclaims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

By the term “substantially” it is meant that the recited characteristic,parameter, or value need not be achieved exactly, but that deviations orvariations, including for example, tolerances, measurement error,measurement accuracy limitations and other factors known to those ofskill in the art, may occur in amounts that do not preclude the effectthe characteristic was intended to provide.

Various embodiments of the present disclosure will be provided toachieve the above-described technical aspects of the present disclosure.In an implementation, defined entities may have the same names, to whichthe present disclosure is not limited. Thus, various embodiments of thepresent disclosure can be implemented with same or ready modificationsin a system having a similar technical background.

In various embodiments of the present disclosure, the term “portableterminal” refers to a portable, mobile electronic device, covering avariety of terminals including a video phone, a portable phone, a smartphone, a Wideband Code Division Multiple Access (WCDMA) phone, aUniversal Mobile Telecommunication System (UMTS) terminal, a PersonalDigital Assistant (PDA), a Portable Multimedia Player (PMP), a DigitalMultimedia Broadcasting (DMB) terminal, an e-book reader, a portablecomputer, e.g., a laptop and a tablet, a digital camera, a MotionPicture Experts Group (MPEG) Audio Layer 3 (MP3) player, and any othersimilar and/or suitable electronic device.

FIG. 3 illustrates a configuration of a communication system accordingto an embodiment of the present disclosure.

Referring to FIG. 3, the communication system includes a portableterminal 301 and an external device 303.

The external device 303 supports Universal Serial Bus (USB) connectivityand Mobile High-Definition Link (MHL) connectivity. When the externaldevice 303 is connected to the portable terminal 301 via a cable 305,the external device 303 provides its specific function to the portableterminal 301. MHL is a technique of decreasing 13 High DefinitionMultimedia Interface (HDMI) lines to 3 lines, especially fortransmission of multimedia data between the portable terminal 301 andthe external device 303.

The external device 303 is also referred to as an accessory and may beany of a TeleVision (TV), a monitor, a beam projector, a touch screen,and the like. For example, if the external device 303 is a TV, then theexternal device 303 may provide a multimedia play function of receivingmultimedia data from the portable terminal 301 and displaying thereceived multimedia data.

Particularly, when the external device 303 is connected to the portableterminal 301 via the cable 305, the external device 303 determineswhether a USB connection message has been received from the portableterminal 301 via a MHL Link Control BUS (CBUS) line of the cable 305.The USB connection message is transmitted to determine whether theexternal device 303 supports USB connectivity. The CBUS line is a singlecable bus that transmits auxiliary data between an MHL source device andan MHL sink device. As shown in FIG. 3, the portable terminal 301 mayserve as an MHL source device and the external device 303 may serve asan MHL sink device.

Upon receipt of the USB connection message, the external device 303determines whether the external device 303 supports USB connectivity.Then the external device 303 generates a USB connection response messagebased on the determination result and transmits the USB connectionresponse message to the portable terminal 301 via the CBUS line. The USBconnection response message is a response to the USB connection messagethat indicates whether the external device 303 supports USBconnectivity. The portable terminal 301 determines whether the externaldevice 303 has been connected to the portable terminal 301 via the cable305.

FIG. 4 illustrates lines between a portable terminal and an externaldevice in a communication system according to an embodiment of thepresent disclosure.

Referring to FIG. 4, the cable 305 between the portable terminal 301 andthe external device 303 includes a CBUS line 401, an MHL Data Minus (DM)line 403, an MHL Data Positive (DP) line 405, a USB DM line 407, and aUSP DP line 409 to support both USB connectivity and MHL connectivity.Specifically, the CBUS line 401, the MHL DM line 403, and the MHL DPline 405 are lines for MHL connectivity and the USB DM line 407 and theUSP DP line 409 are lines for USB connectivity.

If the external device 303 has been connected to the portable terminal301, then the portable terminal 301 determines whether the externaldevice 303 supports MHL connectivity. If the external device 303supports MHL connectivity, then the portable terminal 301 is connectedto the external device 303 by MHL connectivity. Then the portableterminal 301 generates a USB connection message and transmits the USBconnection message to the external device 303 via the CBUS line 401.

The portable terminal 301 receives a USB connection response message asa response to the USB connection message from the external device 303via the CBUS line 401 and determines, from the USB connection responsemessage, whether the external device 303 supports USB connectivity. Ifthe external device 303 supports USB connectivity, then the portableterminal 301 recognizes the external device 303 by executing a USB hostfunction.

The USB host function may refer to a function that enables operationbetween portable terminals, such as a PDA, an MP3 player, a portablephone, and other similar and/or suitable portable electronic devices,without intervention of a main computer. For example, the USB hostfunction may include a data exchange function between the portableterminal 301 and the external device 303, and a battery chargingfunction of the portable terminal 301, when the external device 303 isan auxiliary battery.

FIG. 5 is a block diagram of a portable terminal according to anembodiment of the present disclosure.

Referring to FIG. 5, the portable terminal 301 includes a firstcontroller 501, a first memory unit 503, a first MHL unit 505, a firstUSB unit 507, and a first connector 509. The first MHL unit 505 supportsHDMI, to which MHL is applied. HDMI is one type of uncompressed digitalvideo/audio interface standards. HDMI interfaces between a multimediasource, such as an HDMI-enabled set-top box, an HDMI-enabled DigitalVersatile Disk (DVD) player, and the like, and a device, such as anAudio/Visual (AV) device, a monitor, a digital TV, and the like. MHL isa technique of enabling output of multimedia data from the portableterminal 301 to the external device 303. Multimedia data includes videodata, game data, and any other similar and/or suitable type of data,information, and/or content.

The first USB unit 507 supports USB connectivity. USB is a port standarddeveloped for the connection of Personal Computer (PC) peripherals tocomputers including Intel, Compaq, IBM, DEC, Microsoft, NEC, andNorthern Telecom. USB is widely been used and supports a plug-and-playinterface that connects a portable terminal directly to a peripheralsuch as a joystick, a keyboard, a phone, a scanner, a printer, or thelike.

The first memory unit 503 includes a program memory (not shown) and adata memory (not shown). The program memory stores a booting program andan Operating System (OS) to control overall operations of the portableterminal 301 and the data memory stores data generated during operationsof the portable terminal 301. Especially, the first memory unit 503stores an MHL driver for MHL connectivity and a USB driver for USBconnectivity.

The first connector 509 connects the portable terminal 301 to theexternal device 303 via the cable 305. For example, if the firstconnector 509 is an 11-pin connector, the first connector 509 mayinclude a plurality of pins listed in Table 1.

TABLE 1 Pin 1 2 3 4 5 6 7 8 9 10 11 Function VBUS USB USB Power PowerMHL MHL MHL ID GND USB GND DM DP DM DP (CBUS) ID

In order to support both USB connectivity and MHL connectivity, thefirst connector 509 includes a CBUS pin 511, i.e. Pin 8, an MHL DM pin,i.e. Pin 6, an MHL DP pin, i.e. Pin 7, a USB DM pin, i.e. Pin 2, a USBDP pin, i.e. Pin 3, and a USB ID pin, i.e. Pin 10. Specifically, theCBUS pin 511, i.e. Pin 8, the MHL DM pin, i.e. Pin 6, and the MHL DPpin, i.e. Pin 7 are pins for MHL connectivity, whereas the USB DM pin,i.e. Pin 2, the USB DP pin, i.e. Pin 3, and the USB ID pin, i.e. Pin 10,are pins for USB connectivity.

The first controller 501 provides overall control to the portableterminal 301. Particularly, the first controller 501 determines, basedon a USB connection response message, whether the external device 303includes a USB device and recognizes the USB device of the externaldevice by executing a USB host function according to the determinationresult.

More specifically, the first controller 501 determines whether theportable terminal 301 has been connected to the external device 303 viathe cable 305. If the portable terminal 301 has been connected to theexternal device 303, then the first controller 501 determines whetherthe external device 303 supports MHL connectivity. The first controller501 measures a resistance of a USB ID pin, from among a plurality ofpins included in the first connector 509, and compares the measuredresistance with a predetermined resistance. If the measured resistanceis equal to the predetermined resistance, then the first controller 501determines that the external device 303 supports MHL connectivity.

For example, referring to FIG. 2, if the measured resistance of the USBID pin is 1 KΩ, then the first controller 501 may determine that thefirst connector 509 is connected to an MHL cable and that the externaldevice 303 supports MHL connectivity. If determining that the externaldevice 303 supports MHL connectivity, the first controller 501 activatesthe first MHL unit 505 and connects the portable terminal 301 to theexternal device 303 via MHL connectivity. Then the first controller 501generates a USB connection message and transmits the USB connectionmessage to the external device 303 via the CBUS pin 511 of the firstconnector 509. The USB connection message is generated in a CBUS commandformat and transmitted to determine whether the external device 303supports USB connectivity.

The first controller 501 receives a USB connection response message fromthe external device 303, via the CBUS pin 511 of the first connector509, as a response to the USB connection message. The USB connectionresponse message is generated in a CBUS command format, indicatingwhether the external device 303 supports USB connectivity.

The first controller 501 determines, based on the USB connectionresponse message, whether the external device 303 supports USBconnectivity. To be more specific, if the first controller 501determines that the USB connection response message is a first USBconnection response message by analyzing the USB connection responsemessage, then the first controller 501 determines that the externaldevice 303 supports USB connectivity. If the USB connection responsemessage is a second USB connection response message, then the firstcontroller 501 determines that the external device 303 does not supportUSB connectivity. The first USB connection response message is a messageindicating support of USB connectivity in the external device 303 andthe second USB connection response message is a message indicatingnon-support of USB connectivity in the external device 303.

If the external device 303 supports USB connectivity, then the firstcontroller 501 activates the first USB unit 507, activates a USB hostdriver through the first USB unit 507, and executes a USB host function,thereby recognizing the external device 303. For example, if theexternal device 303 is a Human Interface Device (HID), such as a USBtouch screen, then the first controller 501 may recognize allaccessories supported by the USB host driver by activating the USB hostdriver, and thus may recognize the external device 303 being a touchscreen.

FIG. 6 is a block diagram of an external device according to anembodiment of the present disclosure.

Referring to FIG. 6, the external device 303 is an HDMI-enabled displaydevice that supports both USB connectivity and MHL connectivity. Theexternal device 303 includes a second controller 601, a display unit603, an input unit 605, a second memory unit 607, a second MHL unit 609,a second USB unit 611, and a second connector 613.

The input unit 605 includes alphanumerical keys used to enter numbersand characters and function keys used to set functions. The display unit603 displays an image signal on a screen and displays data requested bythe second controller 601. The display unit 603 may be configured with aLiquid Crystal Display (LCD). In this case, the display unit 603 mayinclude an LCD controller, a memory that stores image data, and an LCDdisplay device. If the LCD is configured into a touch screen, thedisplay unit 603 may act as the input unit 605 and thus display the samekeys as in the input unit 605. However, the present disclosure is notlimited thereto, and the display unit 603 may be any type of suitabledisplay device, such as a Light Emitting Diode (LED) display, an OrganicLED (OLED) display, a Thin-Film Transistor (TFT) display, or any othersimilar and/or suitable type of display.

The second memory unit 607 includes a program memory (not shown) and adata memory (not shown). The program memory stores a booting program andan OS to control overall operations of the external device 303 and thedata memory stores data generated during operations of the externaldevice 303.

The second MHL unit 609 supports HDMI, to which MHL is applied. Thesecond USB unit 611 supports USB connectivity. The second connector 613connects the external device 303 to the portable terminal 301 via thecable 305. For example, if the second connector 613 is an 11-pinconnector, then the second connector 613 may include the plurality ofpins listed in Table 1.

The second controller 601 provides overall control to the externaldevice 303. Particularly, upon receipt of a USB connection message fromthe portable terminal 301, the second controller 601 generates a USBconnection response message and transmits the USB response message tothe portable terminal 301.

More specifically, if the external device 303 is connected to theportable terminal 301 via the cable 305, then the second controller 601activates the second MHL unit 609 and connects the external device 303to the portable terminal 301 by MHL connectivity. Then the secondcontroller 601 determines whether a USB connection message has beenreceived via a CBUS pin 615 of the second connector 613. The USBconnection message is transmitted to determine whether the externaldevice 303 supports USB connectivity.

Upon receipt of the USB connection message, the second controller 601determines whether the external device 303 supports USB connectivity.The second controller 601 generates a USB connection response messagebased on the determination result and transmits the USB connectionresponse message to the portable terminal 301 via the CBUS pin 615 ofthe second connector 613. The USB connection response message is aresponse to the USB connection message, indicating whether the externaldevice 303 supports USB connectivity.

To be more specific, if the external device 303 supports USBconnectivity, then the second controller 601 generates a first USBconnection response message indicating support of USB connectivity inthe external device 303 and transmits the first USB connection responsemessage to the portable terminal 301. If the external device 303 doesnot support USB connectivity, then the second controller 601 generates asecond USB connection response message indicating non-support of USBconnectivity in the external device 303 and transmits the second USBconnection response message to the portable terminal 301.

FIG. 7 is a flowchart illustrating an operation of recognizing anexternal device in a communication system according to an embodiment ofthe present disclosure.

Referring to FIG. 7, the portable terminal 301 is connected to theexternal device 303 via the cable 305 such that there is a connectionbetween the portable terminal 301 and the external device 303 inoperation 701. The portable terminal 301 determines whether the externaldevice 303 supports MHL connectivity in operation 703. If the externaldevice 303 supports MHL connectivity, then the portable terminal 301goes to operation 705 and otherwise, the portable terminal 301terminates the operation of recognizing the external device 303.

The portable terminal 301 connects to the external device 303 by MHLconnectivity such that there is an MHL connection in operation 705 andgenerates a USB connection message in operation 707. The USB connectionmessage is generated to determine whether the external device 303supports USB connectivity.

In operation 709, the portable terminal 301 transmits the USB connectionmessage, to the external device 303, via the CBUS line 401. The CBUSline 401 is a single cable bus through which auxiliary data istransmitted from an MHL source device and an MHL sink device. As shownin FIG. 7, the portable terminal 301 may serve as an MHL source device,whereas the external device 303 may serve as an MHL sink device.

In operation 711, the external device 303 receives the USB connectionmessage, determines whether the external device 303 supports USBconnectivity, and generates a USB connection response message based onthe determination result. The USB connection response message is aresponse to the USB connection message and indicates whether theexternal device 303 supports USB connectivity. The external device 303transmits the USB connection response message to the portable terminal301 via the CBUS line 401 in operation 713.

In operation 715, the portable terminal 301 receives the USB connectionresponse message as a response to the USB connection message anddetermines, based on the USB connection response message, whether theexternal device 303 supports USB connectivity. If the external device303 supports USB connectivity, then the portable terminal 301 goes tooperation 717 and otherwise, the portable terminal 301 terminates theoperation of recognizing the external device 303.

The portable terminal 301 recognizes a USB device of the external device303 by executing a USB host function in operation 717. The USB hostfunction refers to a function that enables operation between portableterminals, such as a PDA, an MP3 player, and a portable phone, withoutintervention of a main computer. For example, the USB host function mayinclude a data exchange function between the portable terminal 301 andthe external device 303, and a battery charging function of the portableterminal 301, when the external device 303 is an auxiliary battery.

FIG. 8 is a flowchart illustrating an operation of recognizing anexternal device in a portable terminal according to an embodiment of thepresent disclosure.

Referring to FIG. 8, the first controller 501 of the portable terminal301 connects the portable terminal 301 to the external device 303 viathe first connector 509 in operation 801 and determines whether theexternal device 303 supports MHL connectivity in operation 803.

In order to determine whether the external device 303 supports MHLconnectivity, the first controller 501 measures the resistance of a USBID pin, from among a plurality of pins included in the first connector509, and compares the measured resistance with a predeterminedresistance. If the measured resistance is equal to the predeterminedresistance, then the first controller 501 determines that the externaldevice 303 supports MHL connectivity. For example, referring to FIG. 2,if the measured resistance of the USB ID pin is 1 KΩ, then the firstcontroller 501 may determine that the first connector 509 is connectedto an MHL cable and that the external device 303 supports MHLconnectivity.

If the first controller 501 determines that the external device 303supports MHL connectivity, then the first controller 501 goes tooperation 805 and otherwise, the first controller 501 terminates theoperation of recognizing the external device 303.

In operation 805, the first controller 501 activates the first MHL unit505 and connects the portable terminal 301 to the external device 303 byestablishing an MHL connection. Then the first controller 501 generatesa USB connection message in operation 807 and transmits the USBconnection message to the external device 303 via the CBUS line of thefirst connector 509 in operation 809. The USB connection message isgenerated in a CBUS command format and transmitted to determine whetherthe external device 303 supports USB connectivity.

In operation 811, the first controller 501 determines whether a USBconnection response message from the external device 303 is received viathe CBUS line of the first connector 509, as a response to the USBconnection message. The USB connection response message is generated ina CBUS command format, indicating whether the external device 303supports USB connectivity.

If the USB connection response message is received, then the firstcontroller 501 goes to operation 813 and otherwise, the first controller501 repeats operation 811.

In operation 813, the first controller 501 determines, based on the USBconnection response message, whether the external device 303 supportsUSB connectivity. If the external device 303 supports USB connectivity,then the first controller 501 goes to operation 815 and otherwise, thefirst controller 501 terminates the operation of recognizing theexternal device 303.

To be more specific, if the first controller 501 determines that the USBconnection response message is a first USB connection response messageby analyzing the USB connection response message, then the firstcontroller 501 determines that the external device 303 supports USBconnectivity. If the USB connection response message is a second USBconnection response message, then the first controller 501 determinesthat the external device 303 does not support USB connectivity. Thefirst USB connection response message is a message indicating support ofUSB connectivity in the external device 303 and the second USBconnection response message is a message indicating non-support of USBconnectivity in the external device 303.

In operation 815, the first controller 501 activates the first USB unit507, activates a USB host driver through the first USB unit 507, andexecutes a USB host function, thereby recognizing a USB device of theexternal device 303. For example, if the external device 303 is an HID,such as a USB touch screen, then the first controller 501 may recognizeall accessories supported by the USB host driver by activating the USBhost driver and thus may recognize the external device 303 being a touchscreen.

FIG. 9 is a flowchart illustrating an operation of transmitting a USBconnection response message in an external device according to anembodiment of the present disclosure.

Referring to FIG. 9, the second controller 601 of the external device303 connects the external device 303 to the portable terminal 301 viathe cable 305 in operation 901. In operation 903, the second controller601 activates the second MHL unit 609, connects the external device 303to the portable terminal 301 by MHL connectivity, and determines whethera USB connection message has been received via the CBUS line of thesecond connector 613 in operation 903. The USB connection message istransmitted to determine whether the external device 303 supports USBconnectivity. Upon receipt of the USB connection message, the secondcontroller 601 goes to operation 905 and otherwise, the secondcontroller 601 repeats operation 903.

In operation 905, the second controller 601 determines whether theexternal device 303 supports USB connectivity. If the external device303 supports USB connectivity, then the second controller 601 goes tooperation 907 and otherwise, the second controller 601 goes to operation909.

In operation 907, the second controller 601 generates a first USBconnection response message indicating support of USB connectivity inthe external device 303 and goes to operation 911. On the other hand,the second controller 601 generates a second USB connection responsemessage indicating non-support of USB connectivity in the externaldevice 303 in operation 909 and goes to operation 911. The secondcontroller 601 transmits the first USB connection response message orthe second USB connection response message, via the CBUS line, to theportable terminal 301 in operation 911.

FIG. 10 illustrates a configuration of a communication system accordingto another embodiment of the present disclosure.

Referring to FIG. 10, the communication system includes a portableterminal 1001, a first external device 1003, and a second externaldevice 1007. The second external device 1007 supports USB connectivity,is connected to the first external device 1003 via a USB cable 1009, andprovides a specific function to at least one of the first externaldevice 1003 and the portable terminal 1001. For example, if the secondexternal device 1007 is a keyboard, the second external device 1007 isused as an input device. Thus, the second external device 1007 transmitsdata related to a user-selected key to at least one of the firstexternal device 1003 and the portable terminal 1001 through the firstexternal device 1003.

The first external device 1003 supports USB connectivity and MHLconnectivity. When the first external device 1003 is connected to theportable terminal 1001 via a cable 1005, the first external device 1003provides its specific function to the portable terminal 1001. MHL is atechnique of decreasing 13 HDMI lines to 3 lines, especially fortransmission of multimedia data between the portable terminal 1001 andthe external device 1003.

The first and second external devices 1003 and 1007 are calledaccessories. The first external device 1003 may be a display devicesupporting MHL connectivity, such as a TV, a monitor, a beam projector,a touch screen, or the like. The second external device 1007 may be adevice supporting USB connectivity, such as a USB memory, an auxiliaryUSB battery, a dongle, a USB mouse, or the like.

Particularly, when the first external device 1003 is connected to theportable terminal 1001 via the cable 1005, the first external device1003 determines whether a USB connection message has been received fromthe portable terminal 1001 via a CBUS line of the cable 1005. The USBconnection message is transmitted to determine whether the firstexternal device 1003 supports USB connectivity. The CBUS is a singlecable bus that transmits auxiliary data between an MHL source device andan MHL sink device. As shown in FIG. 10, the portable terminal 1001 mayserve as an MHL source device and the first external device 1003 mayserve as an MHL sink device.

Upon receipt of the USB connection message, the first external device1003 determines whether the first external device 1003 supports USBconnectivity. Then the first external device 1003 generates a USBconnection response message based on the determination result andtransmits the USB connection response message to the portable terminal1001 via a CBUS line. The USB connection response message is a responseto the USB connection message and indicates whether the first externaldevice 1003 supports USB connectivity. The portable terminal 1001determines whether the first external device 1003 has been connected tothe portable terminal 301 via the cable 1005.

FIG. 11 illustrates lines between a portable terminal and an externaldevice in a communication system according to another embodiment of thepresent disclosure.

Referring to FIG. 11, the cable 1005 between the portable terminal 1001and the first external device 1003 includes a CBUS line 1101, an MHL DMline 1103, an MHL DP line 1105, a USB DM line 1107, and a USP DP line1109 to support both USB connectivity and MHL connectivity.Specifically, the CBUS line 1101, the MHL DM line 1103, and the MHL DPline 1105 are lines for MHL connectivity and the USB DM line 1107 andthe USP DP line 1109 are lines for USB connectivity.

If the first external device 1003 has been connected to the portableterminal 1001, then the portable terminal 1001 determines whether thefirst external device 1003 supports MHL connectivity. If the firstexternal device 1003 supports MHL connectivity, then the portableterminal 1001 is connected to the first external device 1003 by MHLconnectivity. Then the portable terminal 1001 generates a USB connectionmessage and transmits the USB connection message to the first externaldevice 1003 via the CBUS line 1101.

The portable terminal 1001 receives a USB connection response message,as a response to the USB connection message, from the first externaldevice 1003 via the CBUS line 1101 and determines, from the USBconnection response message, whether the first external device 1003supports USB connectivity. If the first external device 1003 supportsUSB connectivity, then the portable terminal 1101 recognizes USB devicesof the first external device 1003 and the second external device 1007,which is connected to the first external device 1003, by executing a USBhost function. For example, if the first external device 1003 includesUSB devices, such as a USB hub and a USB touch screen, then the portableterminal 1001 may recognize the USB hub and the USB touch screen of thefirst external device 1003 via the USB host function.

The USB host function refers to a function that enables operationbetween portable terminals, such as a PDA, an MP3 player, and a portablephone, without intervention of a main computer. For example, the USBhost function may include a data exchange function between the portableterminal 1001 and the first external device 1003, and a battery chargingfunction of the portable terminal 1001, when the first external device1003 is an auxiliary battery.

The portable terminal 1001 uses a specific function provided by thesecond external device 1007 connected directly to the first externaldevice 1003 by a USB enumeration procedure. The USB enumerationprocedure is known in the art and will not be described herein indetail.

FIG. 12 is a block diagram of a portable terminal according to anotherembodiment of the present disclosure.

Referring to FIG. 12, the portable terminal 1001 includes a thirdcontroller 1201, a third memory unit 1203, a third MHL unit 1205, athird USB unit 1207, and a third connector 1209 that includes a CBUS pin1211. The third MHL unit 1205 supports HDMI, to which MHL is applied.HDMI interfaces between a multimedia source, such as an HDMI-enabledset-top box, an HDMI-enabled Digital Versatile Disc (DVD) player, andthe like, and a device such as an Audio Video (AV) device, a monitor, adigital TV, and the like. MHL is a technique of enabling output ofmultimedia data from the portable terminal 1001 to an external device.Multimedia data includes video data, game data, media content data,sound data, image data, and the like. The third USB unit 1207 supportsUSB connectivity.

The third memory unit 1203 includes a program memory and a data memory.The program memory stores a booting program and an Operating System (OS)to control overall operations of the portable terminal 1001 and the datamemory stores data generated during operations of the portable terminal1001. Especially, the third memory unit 1003 stores an MHL driver forMHL connectivity and a USB driver for USB connectivity.

The third connector 1009 connects the portable terminal 1001 to thefirst external device 1003 via the cable 1005. For example, if the thirdconnector 1209 is an 11-pin connector, the third connector 1209 mayinclude the plurality of pins listed in Table 1.

The third controller 1201 provides overall control to the portableterminal 1001. Particularly, the third controller 1201 determines, basedon a USB connection response message, whether an external deviceincludes a USB device and recognizes the USB device of the externaldevice by executing a USB host function according to the determinationresult.

More specifically, the third controller 1201 determines whether theportable terminal 1001 has been connected to the first external device1003 via the cable 1005. If the portable terminal 1001 has beenconnected to the first external device 1003, then the third controller1201 determines whether the first external device 1003 supports MHLconnectivity. The third controller 1201 measures the resistance of a USBID pin, from among a plurality of pins included in the third connector1209, and compares the measured resistance with a predeterminedresistance. If the measured resistance is equal to the predeterminedresistance, then the third controller 1201 determines that the firstexternal device 1003 supports MHL connectivity.

For example, referring to FIG. 2, if the measured resistance of the USBID pin is 1 KΩ, then the third controller 1201 may determine that thethird connector 1209 is connected to an MHL cable and that the firstexternal device 1003 supports MHL connectivity.

If the third controller 1201 determines that the first external device1003 supports MHL connectivity, then the third controller 1201 activatesthe third MHL unit 1205 and connects the portable terminal 1001 to thefirst external device 1003 by MHL connectivity. Then the thirdcontroller 1201 generates a USB connection message and transmits the USBconnection message via the CBUS pin of the third connector 1209. The USBconnection message is generated in a CBUS command format and transmittedto determine whether the first external device 1003 supports USBconnectivity.

The third controller 1201 receives a USB connection response messagefrom the first external device 1003 via the CBUS pin of the thirdconnector 1209, as a response to the USB connection message. The USBconnection response message is generated in a CBUS command format andindicates whether the first external device 1003 supports USBconnectivity.

The third controller 1201 determines, based on the USB connectionresponse message, whether the first external device 1003 supports USBconnectivity. To be more specific, if the third controller 1201determines that the USB connection response message is a first USBconnection response message by analyzing the USB connection responsemessage, then the third controller 1201 determines that the firstexternal device 1003 supports USB connectivity. If the USB connectionresponse message is a second USB connection response message, then thethird controller 1201 determines that the first external device 1003does not support USB connectivity. The first USB connection responsemessage is a message indicating support of USB connectivity in the firstexternal device 1003 and the second USB connection response message is amessage indicating non-support of USB connectivity in the first externaldevice 1003.

If the first external device 1003 supports USB connectivity, then thethird controller 1201 activates the third USB unit 1207, activates a USBhost driver through the third USB unit 1207, and executes a USB hostfunction, thereby recognizing USB devices of the first external device1003.

For example, if the first external device 1003 includes USB devices suchas a USB hub and a USB touch screen, then the portable terminal 1001 mayrecognize all accessories supported by a USB host driver by activatingthe USB host driver and thus may recognize the USB hub and the USB touchscreen of the first external device 1003. As the third controller 1201recognizes the USB hub of the first external device 1003, the thirdcontroller 1201 may recognize a USB device of the second external device1007.

The portable terminal 1001 uses a specific function provided by thesecond external device 1007 connected directly to the first externaldevice 1003 by a USB enumeration procedure.

FIG. 13 is a block diagram of an external device according to anotherembodiment of the present disclosure.

Referring to FIG. 13, the first external device 1003 is an HDMI-enableddisplay device that supports both USB connectivity and MHL connectivity.The first external device 1003 includes a fourth controller 1301, adisplay unit 1303, an input unit 1305, a fourth memory unit 1307, afourth MHL unit 1309, a fourth USB unit 1311, a USB hub 1313, and afourth connector 1315 that includes a CBUS pin 1317.

The input unit 1305 includes alphanumerical keys used to enter numbersand characters and function keys used to set functions. The display unit1303 displays an image signal on a screen and displays data requested bythe fourth controller 1301. The display unit 1303 may be configured withan LCD or any other similar and/or suitable display device type. In thiscase, the display unit 1303 may include an LCD controller, a memory thatstores image data, and an LCD display device. If the LCD is configuredto be a touch screen, then the display unit 1303 may act as the inputunit 1305 and thus display the same keys, similar keys, and/or otherkeys, as in the input unit 1305.

The fourth MHL unit 1309 supports HDMI to which MHL is applied. Thefourth USB unit 1311 supports USB connectivity. The fourth memory unit1307 includes a program memory and a data memory. The program memorystores a booting program and an OS to control overall operations of thefirst external device 1003 and the data memory stores data generatedduring operations of the first external device 1003.

The fourth connector 1315 connects the first external device 1003 to theportable terminal 1001 via the cable 1005. For example, if the fourthconnector 1315 is an 11-pin connector, then the fourth connector 1315may include the plurality of pins listed in Table 1. The USB hub 1313includes at least one USB port and connects the first external device1003 to the second external device 1007 via the USB cable 1009 connectedto a USB port.

The fourth controller 1301 provides overall control to the firstexternal device 1003. Particularly, upon receipt of a USB connectionmessage from the portable terminal 1001, the fourth controller 1301generates a USB connection response message and transmits the USBresponse message to the portable terminal 1001.

More specifically, if the first external device 1003 is connected to theportable terminal 1001 via the cable 1005, then the fourth controller1301 activates the fourth MHL unit 1309 and connects the first externaldevice 1003 to the portable terminal 1001 by MHL connectivity. Then thefourth controller 1301 determines whether a USB connection message hasbeen received via the CBUS pin 1317 of the fourth connector 1315. TheUSB connection message is transmitted to determine whether the firstexternal device 1003 supports USB connectivity.

Upon receipt of the USB connection message, the fourth controller 1301determines whether the first external device 1003 supports USBconnectivity. The fourth controller 1301 generates a USB connectionresponse message based on the determination result and transmits the USBconnection response message to the portable terminal 1001 via the CBUSpin 1317 of the fourth connector 1315. The USB connection responsemessage is a response to the USB connection message and indicateswhether the first external device 1003 supports USB connectivity.

To be more specific, if the first external device 1003 supports USBconnectivity, then the fourth controller 1301 generates a first USBconnection response message indicating support of USB connectivity inthe first external device 1003 and transmits the first USB connectionresponse message to the portable terminal 1001. If the first externaldevice 1003 does not support USB connectivity, then the fourthcontroller 1301 generates a second USB connection response messageindicating non-support of USB connectivity in the first external device1003 and transmits the second USB connection response message to theportable terminal 1001.

FIG. 14 is a flowchart illustrating an operation of recognizing anexternal device in a communication system according to anotherembodiment of the present disclosure.

Referring to FIG. 14, the portable terminal 1001 is connected to thefirst external device 1003 via the cable 1005 in operation 1401. Theportable terminal 1001 determines whether the first external device 1003supports MHL connectivity in operation 1403. If the first externaldevice 1003 supports MHL connectivity, then the portable terminal 1001goes to operation 1405 and otherwise, the portable terminal 1001terminates the operation of recognizing the first external device 1003.

The portable terminal 1001 connects to the first external device 1003 byMHL connectivity such that there is an MHL connection in operation 1405and generates a USB connection message in operation 1407. The USBconnection message is generated to determine whether the first externaldevice 1003 supports USB connectivity.

In operation 1409, the portable terminal 1001 transmits the USBconnection message to the first external device 1003 via the CBUS line1101. The CBUS is a single cable bus through which auxiliary data istransmitted from an MHL source device and an MHL sink device. As shownin FIG. 14, the portable terminal 1001 may serve as an MHL sourcedevice, whereas the first external device 1003 may serve as an MHL sinkdevice.

In operation 1411, the first external device 1003 receives the USBconnection message, determines whether the first external device 1003supports USB connectivity, and generates a USB connection responsemessage based on the determination result. The USB connection responsemessage is a response to the USB connection message and indicateswhether the first external device 1003 supports USB connectivity. Thefirst external device 1003 transmits the USB connection response messageto the portable terminal 1001 via the CBUS line in operation 1413.

In operation 1415, the portable terminal 1001 receives the USBconnection response message as a response to the USB connection messageand determines, based on the USB connection response message, whetherthe first external device 1003 supports USB connectivity. If the firstexternal device 1003 supports USB connectivity, then the portableterminal 1001 goes to operation 1417 and otherwise, the portableterminal 1001 terminates the operation of recognizing the first externaldevice 1003. The portable terminal 1001 recognizes at least one USBdevice of the first external device 1003 and a USB device of the secondexternal device 1007 by executing a USB host function in operation 1417.The USB host function refers to a function that enables operationbetween portable terminals, such as a PDA, an MP3 player, and a portablephone, without intervention of a main computer.

For example, if the first external device 1003 includes USB devices,such as a USB hub and a USB touch screen, then the portable terminal1001 may recognize all accessories supported by a USB host driver byactivating the USB host driver, and thus may recognize the USB hub andthe USB touch screen of the first external device 1003. As the thirdcontroller 1201 recognizes the USB hub of the first external device1003, the third controller 1201 may recognize a USB device of the secondexternal device 1007.

The portable terminal 1001 uses a specific function provided by thesecond external device 1007 connected directly to the first externaldevice 1003 by a USB enumeration procedure.

FIG. 15 is a flowchart illustrating an operation of recognizing anexternal device in a portable terminal according to another embodimentof the present disclosure.

Referring to FIG. 15, the third controller 1201 of the portable terminal1001 connects the portable terminal 1001 to the first external device1003 via the third connector 1209 in operation 1501 and determineswhether the first external device 1003 supports MHL connectivity inoperation 1503.

The third controller 1201 measures the resistance of a USB ID pin, fromamong a plurality of pins included in the third connector 1209, andcompares the measured resistance with a predetermined resistance. If themeasured resistance is equal to the predetermined resistance, then thethird controller 1201 determines that the first external device 1003supports MHL connectivity. For example, referring to FIG. 2, if themeasured resistance of the USB ID pin is 1 KΩ, then the third controller1201 may determine that the third connector 1209 is connected to an MHLcable and that the first external device 1003 supports MHL connectivity.

If the first external device 1003 supports MHL connectivity, then thethird controller 1201 goes to operation 1505 and otherwise, the thirdcontroller 1201 terminates the operation of recognizing the firstexternal device 1003.

In operation 1505, the third controller 1201 activates the third MHLunit 1205 and connects the portable terminal 1001 to the first externaldevice 1003 by establishing an MHL connection. Then the third controller1201 generates a USB connection message in operation 1507 and transmitsthe USB connection message to the first external device 1003 via theCBUS line of the third connector 1209 in operation 1509. The USBconnection message is generated in a CBUS command format and transmittedto determine whether the first external device 1003 supports USBconnectivity.

In operation 1511, the third controller 1201 determines whether a USBconnection response message is received from the first external device1003 via the CBUS line of the third connector 1209, as a response to theUSB connection message. The USB connection response message is generatedin a CBUS command format and indicates whether the first external device1003 supports USB connectivity.

If it is determined, in operation 1511, that the USB connection responsemessage has been received, then the third controller 1201 goes tooperation 1513 and otherwise, the third controller 1201 repeatsoperation 1511.

In operation 1513, the third controller 1201 determines, based on theUSB connection response message, whether the first external device 1003supports USB connectivity. If the first external device 1003 supportsUSB connectivity, then the third controller 1201 goes to operation 1515and otherwise, the third controller 1201 terminates the operation ofrecognizing the first external device 1003.

To be more specific, if the third controller 1201 determines that theUSB connection response message is a first USB connection responsemessage by analyzing the USB connection response message, then the thirdcontroller 1201 determines that the first external device 1003 supportsUSB connectivity. If the USB connection response message is determinedto be a second USB connection response message, then the thirdcontroller 1201 determines that the first external device 1003 does notsupport USB connectivity. The first USB connection response message is amessage indicating support of USB connectivity in the first externaldevice 1003 and the second USB connection response message is a messageindicating non-support of USB connectivity in the first external device1003.

In operation 1515, the third controller 1201 activates the third USBunit 1207, activates a USB host driver through the third USB unit 1207,and executes a USB host function, thereby recognizing at least one USBdevice of the first external device 1003 and the second external device1007 connected directly to the first external device 1003.

For example, if the first external device 1003 includes USB devices,such as a USB hub and a USB touch screen, then the third controller 1021may recognize all accessories supported by a USB host driver byactivating the USB host driver, and thus may recognize the USB hub andthe USB touch screen of the first external device 1003. As the thirdcontroller 1201 recognizes the USB hub of the first external device1003, the third controller 1201 may recognize a USB device of the secondexternal device 1007.

The third controller 1201 uses a specific function provided by thesecond external device 1007 connected directly to the first externaldevice 1003 by a USB enumeration procedure. An operation of transmittinga USB connection response message in an external device according toanother embodiment of the present disclosure is same as the operationillustrated in FIG. 9 and thus an operation of transmitting a USBconnection response message in the first external device 1003 will notbe described herein.

As is apparent from the above description of the present disclosure, allexternal devices supporting USB connectivity may be recognized in acommunication system. All external devices supporting USB connectivitymay be recognized by MSB connectivity in a communication system. Allexternal devices supporting USB connectivity may be recognized using aCBUS line among MHL lines in a communication system.

At this point it should be noted that the various embodiments of thepresent disclosure as described above typically involve the processingof input data and the generation of output data to some extent. Thisinput data processing and output data generation may be implemented inhardware or software in combination with hardware. For example, specificelectronic components may be employed in a mobile device or similar orrelated circuitry for implementing the functions associated with thevarious embodiments of the present disclosure as described above.Alternatively, one or more processors, such as an Integrated Circuit(IC), an Application Specific IC (ASIC), an Erasable Programmable ReadOnly Memory (EPROM), or any other similar and/or suitable hardwaredevice that performs information processing, operating in accordancewith stored instructions may implement the functions associated with thevarious embodiments of the present disclosure as described above. Ifsuch is the case, it is within the scope of the present disclosure thatsuch instructions may be stored on one or more processor and/or computerreadable mediums. Examples of the processor and/or computer readablemediums include a Read-Only Memory (ROM), a Random-Access Memory (RAM),a Compact Disc (CD)-ROMs, magnetic tapes, floppy disks, and optical datastorage devices. The processor and/or computer readable mediums may benon-volatile, and may also be distributed over network coupled computersystems so that the instructions are stored and executed in adistributed fashion. Also, functional computer programs, instructions,and instruction segments for accomplishing the present disclosure can beeasily construed by programmers skilled in the art to which the presentdisclosure pertains.

While it has been described that a connector is an 11-pin connector inthe present disclosure, the connector is not limited to the specificnumber of pins. Thus the connector may be an 18-pin, 22-pin, or anysuitable number of pins connector. In another example, while it has beendescribed that a portable terminal recognizes a first external devicesupporting MHL connectivity and USB connectivity, the first externaldevice is not limited to the specific connection schemes. Thus the firstexternal device may support a connection scheme other than MHLconnectivity and USB connectivity. Further, it has been described in thepresent disclosure that the portable terminal receives a USB connectionmessage via a CBUS line being a cable line from the external device.However, communication between the portable terminal and the externaldevice is not limited to wired communication. Thus, the portableterminal may transmit a USB connection message or receive a USBconnection response message in a radio frequency.

While the present disclosure has been shown and described with referenceto various embodiments thereof, it will be understood by those skilledin the art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the present disclosure asdefined by the appended claims and their equivalents.

What is claimed is:
 1. An apparatus comprising: a connector connected toan external device; and a controller configured to: determine whether aportable terminal is connected to the external device, transmit aconnection message, if it is determined that the portable terminal isconnected to the external device through the connector, the connectionmessage asking whether the external device supports a second connectionscheme, to the external device by using a first connection scheme,receive a connection response message from the external device inresponse to the connection message, determine, based on the connectionresponse message, whether the external device supports the secondconnection scheme, and recognize at least one device supporting thesecond connection scheme in the external device by activating the secondconnection scheme, if the external device supports the second connectionscheme.
 2. The apparatus of claim 1, wherein the first connection schemeis Mobile High-Definition Link (MHL) connectivity and the secondconnection scheme is Universal Serial Bus (USB) connectivity.
 3. Theapparatus of claim 2, wherein the connector includes a MHL Data Plus(DP) line, a MHL Data Minus (DM) line, a USB DP line, a USB DM line, anda Control BUS (CBUS) line.
 4. The apparatus of claim 2, wherein thecontroller transmits the connection message and receives the connectionresponse message via a Control BUS (CBUS) line of the connector.
 5. Theapparatus of claim 2, wherein the controller recognizes at least one USBdevice of the external device by executing a USB host function.
 6. Anapparatus for recognizing an external device in a portable terminal, theapparatus comprising: a connector connected to the external device; anda controller configured to: determine whether the portable terminal isconnected to the external device; transmit a connection message, if itis determined that the portable terminal is connected to the externaldevice through the connector, the connection message asking whether theexternal device supports Universal Serial Bus (USB) connectivity to theexternal device by using Mobile High-Definition Link (MHL) connectivityvia a Control BUS (CBUS) line of the connector, receive a connectionresponse message from the external device in response to the connectionmessage via the CBUS line, determine, based on the connection responsemessage, whether the external device supports USB connectivity, andrecognize at least one USB device of the external device by executing aUSB host function, if the external device supports USB connectivity. 7.An apparatus for recognizing a portable terminal in an external device,the apparatus comprising: a connector connected to the portable device;and a controller configured to: receive a connection message from theportable terminal by using a first connection scheme, if it isdetermined that the external device is connected to the portableterminal through the connector, the connection message asking whetherthe external device supports a second connection scheme, generate aconnection response message indicating whether the external devicesupports the second connection scheme in response to the connectionmessage, and transmit the connection response message to the portableterminal by using the first connection scheme.
 8. The apparatus of claim7, wherein the first connection scheme is Mobile High-Definition Link(MHL) connectivity and the second connection scheme is Universal SerialBus (USB) connectivity.
 9. The apparatus of claim 8, wherein thecontroller receives the connection message and transmits the connectionresponse message via a Control BUS (CBUS) line of the connector.
 10. Anapparatus for recognizing a portable terminal in an external device, theapparatus comprising: a connector connected to the portable device; anda controller configured to: receive a connection message from theportable terminal by using Mobile High-Definition Link (MHL)connectivity via a Control BUS (CBUS) line of the connector, if it isdetermined that the external device is connected to the portableterminal through the connector, the connection message asking whetherthe external device supports Universal Serial Bus (USB) connectivity,generate a connection response message indicating whether the externaldevice supports USB connectivity in response to the connection message,and transmit the connection response message to the portable terminalvia the CBUS line.
 11. A method of recognizing an external device in aportable terminal, the method comprising: determining whether theportable terminal is connected to the external device; transmitting, ifit is determined that the portable terminal is connected to the externaldevice through a connector, a connection message asking whether theexternal device supports a second connection scheme to the externaldevice by using a first connection scheme; receiving a connectionresponse message in response to the connection message from the externaldevice; determining, based on the connection response message, whetherthe external device supports the second connection scheme; andrecognizing at least one device supporting the second connection schemein the external device by activating the second connection scheme, ifthe external device supports the second connection scheme.
 12. Themethod of claim 11, wherein the first connection scheme is MobileHigh-Definition Link (MHL) connectivity and the second connection schemeis Universal Serial Bus (USB) connectivity.
 13. The method of claim 12,wherein the connection message is at least one of transmitted andreceived via a Control BUS (CBUS) line of the connector.
 14. The methodof claim 12, wherein the recognizing of the at least one devicesupporting the second connection scheme comprises recognizing at leastone USB device of the external device by executing a USB host function.15. A method of recognizing an external device in a portable terminal,the method comprising: determining whether the portable terminal isconnected to the external device; transmitting, if it is determined thatthe portable terminal is connected to the external device through aconnector, a connection message asking whether the external devicesupports Universal Serial Bus (USB) connectivity to the external deviceby using Mobile High-Definition Link (MHL) connectivity via a ControlBUS (CBUS) line of the connector; receiving a connection responsemessage in response to the connection message from the external devicevia the CBUS line; determining, based on the connection responsemessage, whether the external device supports USB connectivity; andrecognizing at least one USB device of the external device by executinga USB host function, if the external device supports USB connectivity.16. A method of recognizing a portable terminal in an external device,the method comprising: receiving, if it is determined that the externaldevice is connected to the portable terminal through a connector, aconnection message asking whether the external device supports a secondconnection scheme from the portable terminal by using a first connectionscheme; generating a connection response message indicating whether theexternal device supports the second connection scheme in response to theconnection message; and transmitting the connection response message tothe portable terminal by using the first connection scheme.
 17. Themethod of claim 16, wherein the first connection scheme is MobileHigh-Definition Link (MHL) connectivity and the second connection schemeis Universal Serial Bus (USB) connectivity.
 18. The method of claim 17,wherein the connection message is at least one of received andtransmitted via a Control BUS (CBUS) line of the connector.
 19. A methodof recognizing a portable terminal in an external device, the methodcomprising: receiving, if it is determined that the external device isconnected to the portable terminal through a connector, a connectionmessage asking whether the external device supports Universal Serial Bus(USB) connectivity from the portable terminal by using MobileHigh-Definition Link (MHL) connectivity via a Control BUS (CBUS) line ofthe connector; generating a connection response message indicatingwhether the external device supports USB connectivity in response to theconnection message; and transmitting the connection response message tothe portable terminal via the CBUS line.